Turbicellepora hansenae Denisenko, 2016, sp. n.

<i>Turbicellepora hansenae</i> sp. n. (Fig. 2 a–g) <p> <b>Material examined.</b> <i>Holotype</i>: ZMUC-BRY-104, fragment of colony, collected by a Canadian expedition research vessel, the Canadian Coast Guard Ship <i>Martha Black</i> at 60°22.3' N, 48°22.19' W, 886–932 m, March 2012.</p> <p> <b>Etymology.</b> Honorific for the late Danish bryozoologist Karen Emilie Bille Hansen (6 May 1919 – 27 December 2010).</p> <p> <b>Description.</b> Colonies somewhat irregular and nodular, slightly yellowish, comprising 30 x 40 mm in size. Zooids semi-vertical in colony, highly distinct owing to deep interzooidal furrows (Fig. 2 a, b), of variable size (0.7–1.0 x 0.5–0.7 mm (Table 1). Frontal shield thick, smooth, with even slope and sparse marginal pores (Fig. 2 c, d). Primary orifice transversely suboval, wider than high with fairly deep wide U-shaped sinus with sloping sides occupying much of proximal border (Fig. 2, b). Peristome of moderate height, rounded, asymmetrical, partly concealing primary orifice (Fig.</p> <p>2b, d). Oral avicularia 1–2, relatively large, with triangular mandible, located laterally near proximal part of orifice as continuation of peristome. Internal base of avicularian cystid wide, with 3 communication pores located on one side only; terminal (frontal) part of avicularium narrower, approaching form of a truncated cone. Rostrum directed frontolaterally, oval-triangular with tip hooked apically, crossbar complete, lacking columella (Fig. 2 c, e). Additional similar columnar avicularia sporadically developed on frontal shields, these smaller in size, with rostrum directed proximally (Fig. 2 d, e). A third type of adventitious avicularium present in ovicellate zooids, located in distal part of orifice (Fig. 2 d, f), with prominent long, curved cystid, arching over ovicell opening; with complete crossbar and small semicircular mandible. Vicarious avicularium immersed, found only once, drop-like in form, with complete crossbar (Fig. 2 g). Ovicell subglobular, prominent, sometimes with slight peak or crest in central part, with up to 20–25 unevenly distributed pseudopores (Fig. 2 d–f).</p>Published as part of <i>Denisenko, Nina V., 2016, Two new species of the genus Turbicellepora Ryland, 1963 (Bryozoa: Celleporidae) found on Lophelia coral from the Greenland slope, pp. 177-182 in Zootaxa 4066 (2)</i> on pages 179-180, DOI: 10.11646/zootaxa.4066.2.6, <a href="http://zenodo.org/record/255455">http://zenodo.org/record/255455</a&gt

Reteporella watersi Denisenko et al. 2016

Reteporella watersi (Nordgaard, 1907) (Fig. 5; Table 3) Retepora beaniana var. watersi Nordgaard, 1907: p. 16; Kluge 1962, p. 529, 530, fig. 370. Reteporella watersi: Hayward 1994: p. 195, fig. 8A, B; Hayward & Ryland 1996: p. 111, fig. 3B; Hayward & Ryland 1999: p. 376, 377, fig. 178A–C. Material examined. ZIN 4 /50741, one colony; Stn 2016_PA_4_40 (61.9967333475749° N; ‒ 41.0106666664283° W; 234 m; T 3.9 °C); MT Paamiut, collected by Alfredo III trawl; fish-shrimp trawl assessment survey. July 2016. ZIN 5 /50745, one colony fragment; Stn 2016_PA_1_22 (64.5355499903361° N; ‒ 55.1436500072479° W; 563 m; T 4.12 °C); MT Paamiut, collected by BEAMTRAWL; fish-shrimp trawl assessment survey. July 2016. Description. The colony is reticulate, funnel-shaped, thickly calcified, robust and matte, up to 50 x 40 mm in size. The branches consist of 3–5 alternate series of zooids, increasing twice in width at points of fusion. Fenestrulae are relatively small, approximately 0.7‒0.9 mm long by 0.2–0.6 mm wide (Fig. 5A; Table 3). The basal surface is covered by kenozooids delimited by prominent vibices (Fig. 5B); the frontal and abfrontal surfaces are deeply pitted with a honeycomb structure. Autozooids (L = 0.35–0.75 mm; W = 0.25–0.42 mm) are located in the inner part of the funnel and delimited by sutures. Several large areolar pores are located near the zooidal margins. The orifice is wider than long, with a straight proximal margin; the upper distal rim is smooth and with short blunt denticles below (Fig. 5C). The orifice is partly hidden by a peristome, which has two unequal lobes that close to form a circular pseudosinus. The larger lobe bears an oval avicularium directed proximolaterally. The suboral avicularium is more or less parallel to the zooidal surface with a tall rim, and a few teeth on the distal rostrum; it has a complete crossbar without columella; the palate is a narrow shelf (Fig. 5C, D, F). Oral spines were not observed. The frontal avicularia are slightly smaller than the suboral ones, oval or roundish with complete crossbar and no columella. The ovicell is immersed, longer than wide, with a pronounced quadrate labellum and an elongate median fissure, mostly covered by pitted extrazooidal calcification during ontogeny (Fig. 5E). Remarks. The suite of characters observed in R. watersi, recently obtained from around Greenland, fits well with previous descriptions of specimens from the Faroe area (cf. Hayward 1994; Hayward & Ryland 1996, 1999). Nevertheless, some discrepancies in skeleton morphology were observed, such as the absence of oral spines in our specimens, which were also lacking in the description by Kluge (1962), as well as in the original description of the species by Nordgaard (1907). The measurements of the specimens analyzed here are also different from those presented in the literature, where zooids and orifices are narrower. Distribution. Sublittoral, deeper than 200 m in the waters south and northwest of Greenland. Around Faroe Islands at 68 stations, and in Iceland waters at 80 stations, at depths between 210 and 1112 m.Published as part of Denisenko, Nina V., 2022, New species and new records of Reteporella (Bryozoa: Cheilostomatida) from Greenland waters, pp. 530-542 in Zootaxa 5129 (4) on pages 538-540, DOI: 10.11646/zootaxa.5129.4.3, http://zenodo.org/record/650400

Turbicellepora greenlandica Denisenko, 2016, sp. n.

<i>Turbicellepora greenlandica</i> sp. n. (Fig. 1, a–f) <p> <b>Material examined.</b> <i>Holotype</i>: ZMUC-BRY-103, fragment of colony, collected by a Canadian expedition research vessel, the Canadian Coast Guard Ship <i>Martha Black</i> at 60°22.3' N, 48°22.19' W, 886–932 m, March 2012. <i>Paratype</i>: ZIN – 1/50641, two parts of another colony, collection data as for holotype.</p> <p>N Mean±SD Min-Max</p> <p> <i>Turbicellepora greenlandica</i> <b>sp. n.</b></p> <p> Autozooid length 15 0.95±0.05 0.82-1.06 Autozooid width 15 0.58±0.04 0.55-0.65 Primary orifice anter width 8 0.13±0.03 0.18-0.02 Primary orifice anter length 8 0.15±0.02 0.15-0.16 Oral avicularium length 10 0.13±0.02 0.13-0.02 Oral avicularium width 10 0.09±0.01 0.09-0.10 Vicarious avicularium length 5 0.46±0.01 0.45-0.47 Vicarious avicularium rostral width 5 0.31±0.01 0.27-0.31 Vicarious avicularium postmandibular width 5 0.12±0.07 0.11-0.01 <i>Turbicellepora hansenae</i> <b>sp. n.</b></p> <p> Autozooid length 8 0.84±0.03 0.74-0.90 Autozooid width 8 0.62±0.05 0.50-0.71 Primary orifice anter width 8 0.19±0.02 0.17-0.22 Primary orifice anter length 8 0.16±0.02 0.14-0.17 Oral avicularium length 8 0.21±0.07 0.18-0.24 Oral avicularium width 8 0.13±0.05 0.12-0.15 Vicarious avicularium length 1 - 0.42 Vicarious avicularium rostral width 1 - 0.33 Vicarious avicularium postmandibular width 1 - 0.11 <b>Etymology.</b> Alluding to the provenance of the species.</p> <p> <b>Description.</b> Colonies partly laminar or lumpy, white, comprising small patches 30 x 40 mm in size. Zooids situated in horizontal plane or semi-vertical, rising in their distal part, convex, highly distinguishable because of deep interzooidal furrows (Fig. 1 a), large (0.8–1.0 x 0.5–0.6 mm (Table 1). Frontal shield thin, weakly textured, with sparse marginal pores (Fig 1 b). Primary orifice transversely suboval, wider than long, the wide sinus occupying much of proximal border, with sloping sides (Fig. 1 c, e). Peristome raised, thin, lower midproximally and flanked by lateral lobes when fully formed (Fig. 1 b, d, f). Usually 1 peristomial oral avicularium, rarely 2, prominent, subcolumnar, with triangular mandible (Fig. 1 d, e); base of avicularian cystid oval, narrowing frontally to subconical, connected with zooids by a single pore. Avicularium surface inclined to orifice, its rostrum directed frontolaterally at angle of 45º to zooidal frontal shield. Additional subcolumnar avicularia sporadically developed on frontal shields of autozooids at distal corners, not far from peristome; these of similar shape to oral avicularia (Fig. 1 b), but can be larger or smaller. Both avicularium types with crossbar lacking columella; rostra triangular, slightly hooked apically. Vicarious avicularia prominent, frequent, large, pyriform, with narrow proximal part and spatulate mandible; crossbar without columella but small protuberances may be seen on (Fig. 1 f). Ovicell prominent, subglobular on zooidal surface, slightly variable in form, being sometimes longer than wide, with 20–25 pseudopores (Fig. 1 d, f).</p> <p> <b>Distribution.</b> Southern part of Davis Strait, southwest of Greenland, 886– 932 m.</p>Published as part of <i>Denisenko, Nina V., 2016, Two new species of the genus Turbicellepora Ryland, 1963 (Bryozoa: Celleporidae) found on Lophelia coral from the Greenland slope, pp. 177-182 in Zootaxa 4066 (2)</i> on pages 178-179, DOI: 10.11646/zootaxa.4066.2.6, <a href="http://zenodo.org/record/255455">http://zenodo.org/record/255455</a&gt

Zoobenthos and oceanographical parameters in the Kemskaya Guba (Bay) - estuary of the Kem' River entering the Onega Bay, White Sea

Data on distribution of zoobenthos in the Kemskaya Guba (or Kemskaya Bay - the estuary of the Kem' River entering the Onega Bay of the White Sea), which is strongly influenced by river runoff, are presented. The number of species at sampling stations varied from 4 to 65. Density of communities and zoobenthos biomass varied from 342±68 to 4293±96 #/m**2 and from 0.418±0.081 to 1975.22±494.36 g/m**2, respectively. Shannon index values varied between 1.19 to 4.7 bit/ind. At the upper part of the estuary, detritivores dominated, while in the central part and at outlets sestonophages prevailed. Changes in quantitative parameters of the zoobenthos along gradient of water salinity were traced, and relations of these parameters with seven other environmental factors were revealed. It was found that species composition, biodiversity, and trophic structure of the zoobenthos significantly correlated with some of parameters mentioned above. Multiple regression analysis was used to assess combined effect of factors, and it revealed which of them played a determining role in Kemskaya Guba: for species composition - depth, water color, and total concentration of suspended matter; for number of species - contents of <0.01 mm grain size (pelite) fraction and organic carbon in bottom sediments. Biomass depended on water salinity, water chromaticity, and organic carbon contents in bottom sediments and suspended matter. Values of the Shannon index of diversity are determined by water color, and contents of organic carbon and pelite fraction in bottom sediments. Calculations of ecological stress values revealed two zones with unstable state of the zoobenthos

New Cheilostomata (Bryozoa) species from sublittoral and bathyal zones off the Faroe Islands, with some comments on allied taxa

Denisenko, Nina V. (2018): New Cheilostomata (Bryozoa) species from sublittoral and bathyal zones off the Faroe Islands, with some comments on allied taxa. Zootaxa 4375 (1): 116-126, DOI: https://doi.org/10.11646/zootaxa.4375.1.

Turbicellepora Ryland 1963

&lt;i&gt;Turbicellepora&lt;/i&gt; Ryland, 1963 &lt;p&gt; &lt;b&gt;Type species.&lt;/b&gt; &lt;i&gt;Cellepora coronopus&lt;/i&gt; S.V. Wood, 1844.&lt;/p&gt;Published as part of &lt;i&gt;Denisenko, Nina V., 2016, Two new species of the genus Turbicellepora Ryland, 1963 (Bryozoa: Celleporidae) found on Lophelia coral from the Greenland slope, pp. 177-182 in Zootaxa 4066 (2)&lt;/i&gt; on page 178, DOI: 10.11646/zootaxa.4066.2.6, &lt;a href="http://zenodo.org/record/255455"&gt;http://zenodo.org/record/255455&lt;/a&gt

Reteporella obscura Denisenko 2022, n. sp.

Reteporella obscura n. sp. (Fig. 2; Table 1) Material examined. Holotype: ZIN1 /50742, one colony;Stn 2016_PA_2_151 (64.52786668° N, ˗ 54.7776999791463° W; 277 m; T 3.934 °C); collected by BEAMTRAWL, MT Paamiut, fish-shrimp trawl assessment survey. July 2016. Paratype: ZIN 2 / 50747; colony fragment; Stn 2016_PA_1_16 (64.35196667° N; ˗ 53.8765166600545° W; 165 m; T 1.575 °C); collected by BEAMTRAWL, MT Paamiut, fish-shrimp trawl assessment survey. July 2016. Diagnosis. Colony reticulate, broadly fan-shaped; fenestrulae large; different levels of granulation on frontal and abfrontal surfaces. Trabeculae of variable length, with 2‒3 series of alternating zooids, doubling at bifurcations. Zooids flat, with 3‒5 large marginal pores; marginal zooids near fenestrulae with 5‒6 marginal pores. Orifice semicircular, approximately as wide as long with rounded condyles and slightly prominent proximal edge; distal rim smooth with a well-developed row of denticles in its lower part. Spines paired, one on each side of orifice at about mid-length; peristome asymmetric with a widely open pseudosinus; larger lobe with a small circular avicularium directed terminally-proximally relative to the zooidal surface; rostrum finely toothed, crossbar complete, columella absent, cystid invisible, mandible edge raised. Frontal avicularia sporadic, oval and relatively small, crossbar complete, columella absent, palate forming a more or less developed shelf, distal uncalcified area semicircular. Abfrontal avicularia rare, circular, distal part raised with fine denticulation. Ovicells longer than wide with long fissure, and relatively narrow labellum. Etymology. Latin “ obscura ” (unclear), alluding to the possibility of misidentification with closely related species of Reteporella. Description. The colony is 40–50 mm high, broadly fan-shaped. The fenestrulae are mainly oval, twice as long as wide, commonly 1.1 x 0.53 mm (Fig. 2A, B; Table 1). The trabeculae (0.85 x 1.05 mm) consisting of two to three alternating, longitudinal series of autozooids, doubled at points of trabecular bifurcations (Fig. 2A). The abfrontal surface of the colony is densely and finely granulated, covered by flat kenozooids clearly delimited by vibices, and with rare round avicularia (Fig. 2B). One horn-shaped kenozooid (about 0.5 mm in length) with a rounded avicularium was observed (Fig. 2A, C, G). The granulation on the frontal side is comparatively coarser but less dense than that on the abfrontal surface (Fig. 2A, B). Autozooids are elongate hexagonal, delimited by mainly straight edges, and occasionally by sutures, obscured by later calcification; autozooids size is about 0.49 x 0.275 mm, but width and length vary considerably especially in areas of bifurcation (Fig. 2D, J; Table 1). The autozooids have few (2–3) large, distinct marginal pores but zooids located near fenestrulae have an additional row of 5–6 pores near the external edge (Fig. 2D, J). The primary orifice is semicircular with slightly prominent proximal edge, slightly wider than long (mean size 0.094 x 0.100 mm); the distal margin of the orifice is smooth along its upper edge and with well pronounced denticles along its lower margin; condyles are large and rounded. A pair of oral spines is present, one on each side of the orifice at about mid-length. The peristome hides the orifice in frontal view and consists of two unequal lobes forming an open sinus (Fig. 2D–F). A single circular avicularium is present on its rim, mid-proximally, 0.041 mm long, proximally directed and oblique to the frontal surface (Fig. 2F). The avicularium is immersed in the peristome, the avicularian cystid is invisible, and the distal rim of the mandible is finely toothed. Frontal avicularia are sporadic, oval (0.084 x 0.053 mm) demarcated by a raised rim (Fig. 2D, J); the distal margin of the rostrum is smooth, the mandible is semi-oval, the crossbar is complete without columella, and the distal uncalcified area is semicircular. Abfrontal avicularia are small, nearly circular (diameter 0.042 mm); the distal margin of the rostrum is toothed, the mandible is semicircular, and the crossbar is complete without columella. Ovicells are located above the distal rim of the orifice; ooecia are longer than wide, with an elongate median fissure and a narrow squared labellum; ooecia become partly obscured by secondary calcification in late ontogeny (Fig. 2I). Remarks. Reteporella obscura n. sp. was found in the sublittoral zone, at two stations in the Davis Strait of SW Greenland.At first glance, the new species is very similar to R. beaniana, which is widely distributed in the Arctic Atlantic, in the appearance of colonies and zooids, in the morphology of the secondary orifice and peristome with widely open pseudosinus, and in having a pair of orificial spines. However, the new species is distinguishable from R. beaniana in having a distinct granulation on both surfaces of the colony, and in the shape of the primary orifice which is bell-shaped in R. beaniana and semicircular in R. obscura n. sp. Differences are also observed in the shape of the condyles, which are roundish in the new species and rounded triangular in R. beaniana (Hayward & Ryland 1996, 1999). The suboral avicularium of the new species is round with an indistinct cystid, whereas in R. beaniana it is oval and the cystid is prominently emerging above the frontal shield. In addition, Reteporella obscura n. sp. is characterized by globular ovicells, longer than wide with a prominent but relatively narrow labellum, whereas R. beaniana has ovicells that are wider than long, and with an arched aperture, and a flattened frontal surface (Hayward & Ryland 1996, 1999). Distribution. Lower sublittoral zone (165–277 m), Davis Strait (SW of Greenland).Published as part of Denisenko, Nina V., 2022, New species and new records of Reteporella (Bryozoa: Cheilostomatida) from Greenland waters, pp. 530-542 in Zootaxa 5129 (4) on pages 532-535, DOI: 10.11646/zootaxa.5129.4.3, http://zenodo.org/record/650400

Reteporella vitta Denisenko 2022, n. sp.

Reteporella vitta n. sp. (Figs 3, 4; Table 2) Material examined. Holotype: ZIN 1 /50743, one colony; Stn 2016_PA_5_58 (64.8872833251953° N, ˗ 34.5760166803996° W; 948 m; T 3.24 °C); collected by Alfredo III trawl, MT Paamiut, fish-shrimp trawl assessment survey. July 2016. Diagnosis. Reteporella with delicate, reticulate colony, large fenestrulae and dimpled frontal and abfrontal surfaces. Trabeculae long, consisting of one to three alternating series of autozooids without doubling at bifurcations. Autozooids with 1‒3 large marginal pores and with wavy edges; primary orifice semicircular, slightly wider than long; condyles large, robust, trapezoidal; spines absent; peristome intermediately tall, consisting of two unequal lobes, often closed forming a roundish spiramen. Circular suboral avicularium with prominent chamber located on larger peristomial lobe; distal rostrum finely denticulate or smooth, crossbar complete, columella absent, palate narrow; frontal avicularia oval with complete crossbar, no columella and narrow palate. Abfrontal avicularia nearly circular, distal rostral margin denticulate, without palate. Ovicells prominent, sometimes with a short labellum and with closed fissure in late ontogeny. Etymology. Latin “ vitta ” (lacy), alluding to the delicate, graceful, lacy appearance of the colony. Description. The colony is reticulate, delicate and shiny. The frontal sides of the autozooids face towards the inner side of the rosette, as it is common in Reteporella species. As the colony grows, it develops as asymmetrical lateral lobes that curl outwards and backwards, transforming the colony into a funnel, in which, once the lobes come into contact with each other, the abfrontal side becomes the inner surface of the funnel, and the frontal side its outer surface (Fig. 3A, B). The colony is up to 60 x 25 mm in size; the fenestrulae are large, elongate, rhomboidal, polygonal or oval; their length (1.9‒2.4 mm) is twice their width (0.7‒1.05 mm). Both surfaces of the colony (i.e. zooidal frontal shield and the abfrontal surface) are regularly and densely covered by polygonal depressions marked by thin ridges. The abfrontal side is covered with kenozooids delimited by clearly visible vibices. The trabeculae are long (0.6–1.9 mm) and narrow (0.24–0.65), consisting of 1–3 alternating longitudinal series of autozooids (Fig. 4A, B). Autozooids are elongate, hexagonal; the frontal shield is shiny and slightly convex with wavy edges delimited by sutures, somewhat blurred in zooids with ovicells (Fig. 4D, E). Autozooids vary considerably in size (Table 2) but they are usually about 0.75–0.85 mm long by about 0.25 mm wide. The dimpled frontal surface bears usually 1‒2 large marginal pores, with or without a low rim. The primary orifice, partly hidden by the peristome, is semicircular, slightly wider (0.12 mm) than long (0.08 mm) (Fig. 4C, D); the proximal edge is straight, the distal margin is smooth along its upper edge, but has a slightly immersed row of minute blunt denticles better pronounced in ovicell-bearing zooids. The condyles are large, blunt, trapezoidal (Fig. 4C), deeply immersed and poorly visible when viewed using a stereomicroscope. Oral spines were not observed in the analyzed specimen. The peristome hides half of the orifice and consists of two unequal lobes, open or closed, forming in the latter case a small spiramen (Fig. 4C, D), which often disappears due to progressing calcification, regardless of the location of the zooid in the colony. On the larger peristomial lobe there is a small, rounded (Fig. 4C, D) suboral avicularium (about 0.047 mm in diameter) with a toothed distal rostrum, complete crossbar without columella, the palate as a narrow shelf, and semicircular mandible (Fig. 4D–F). The suboral avicularium is generally oriented proximally and obliquely to the colony surface, and its cystid protrudes noticeably. Frontal avicularia are also small, although slightly larger than the suboral ones, oval, 0.083 x 0.056 mm, parallel to the frontal surface, with smooth rostrum and complete crossbar, palate as a narrow shelf, uncalcified semicircular area proximal to the crossbar often larger than the distal semi-elliptical one, and semicircular mandible (Fig. 4E). Abfrontal avicularia (Fig. 4B) are small, nearly circular (diameter 0.042 mm), with the distal margin of the rostrum toothed, complete crossbar without columella, and semicircular mandible (Fig. 4G). The ovicell is prominent, the length (0.235 mm) slightly greater than the width (0.228 mm), its proximal surface is slightly flattened, sometimes with a short, weak labellum, but the labellum is usually lacking. The median fissure closes during ovicell formation, leaving in its place a long, narrow median depression in the proximal half of the ooecium (Fig. 4D, E). Remarks. Despite the large volume of material processed, the new species R. vitta n. sp. was found only in one sample. The new species has a dimpled surface as R. watersi and R. rara from the North Atlantic, but in contrast to these species, which have robust colonies and a dull surface (Jullien & Calvet 1903; Hayward 1994; Hayward & Ryland 1996, 1999), the colony of R. vitta n. sp. is delicate, shiny and with large fenestrulae. Based on the descriptions by Hayward & Ryland (1996, 1999) and Jullien & Calvet (1903), the fenestrulae in R. vitta n. sp. are 2.3 times larger than those in R. watersi and R. rara. The arrangement of autozooids within the colony also differs among these species. In R. vitta n. sp., autozooids form a series of 1–3 rows, remaining constant in width at bifurcations, whereas there are 3–5 rows of autozooids in R. watersi that double in number at bifurcations. Reteporella vitta n. sp. also differs from R. watersi and R. rara in the size of autozooids (see Tables 3, 4). For instance, the autozooids in R. vitta n. sp. are 1.5 times longer than in R. watersi and R.rara. The primary orifice in all three species is wider than long, but the proportions are different with the primary orifice of R. vitta n. sp. and R. watersi smaller than that of R. rara (c. 0.137 x 0.2 mm; B. Berning, pers. comm. 2022), in which the proximal edge is slightly more convex than in the new species. The morphology of the condyles differs as well among the three species. Moreover, although all species have a small suboral avicularium, it is oval in R. watersi and in R. rara, and round in R. vitta n. sp. The orientation of the peristomial avicularium is also different in the species under consideration; in R. vitta n. sp. and R. rara, it is oriented terminally to the autozooidal surface, while in R. watersi, the rostrum is nearly parallel to the frontal autozooidal surface. The location of the suboral avicularium within the peristome also differs in these species. In R. watersi and R. rara the avicularian chamber is not visible, but in R. vitta n. sp. it is prominent and clearly raised above the frontal autozooidal surface. The ooecium of R. watersi has an open elongate fissure and a conspicuous labellum, whereas in R. vitta n. sp. the fissure is closed and the labellum is small or absent. In R. vitta n. sp., the ectooecium closes immediately as the ooecium forms, and only an elongate, droplet-shaped depression resembling a fissure is evident on the surface. The ooecium in R. watersi has a conspicuous labellum, whereas in R. vitta n. sp. the labellum is small or absent. Distribution. Upper continental slope of SE Greenland.Published as part of Denisenko, Nina V., 2022, New species and new records of Reteporella (Bryozoa: Cheilostomatida) from Greenland waters, pp. 530-542 in Zootaxa 5129 (4) on pages 535-538, DOI: 10.11646/zootaxa.5129.4.3, http://zenodo.org/record/650400